For example, a mouse model study showed that coinfection with IAV and HRV caused milder influenza but did not reduce IAV shedding [8], whereas coinfection with IAV and mouse hepatitis virus strain 1, a murine coronavirus, attenuated disease presentation and reduced IAV replication [7, 8], and this was associated with IFN upregulation. This evidence concerns the gene IFNA1 and influenza.